/*
 * Copyright 2009 Original Author(s)
 * 
 * This file is part of Kommando
 * 
 * Kommando is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * Kommando is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with Kommando.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.kommando.core.search;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.kommando.core.HistoryTracker;
import org.kommando.core.catalog.CatalogObject;
import org.kommando.core.search.ranking.DefaultStringScorer;
import org.kommando.core.search.ranking.StringScorer;

/**
 * The {@link CatalogObjectSearcher} is responsable for filtering and sorting a {@link List} of {@link CatalogObject}s.
 * <p>
 * The filtering is done based on a query and an array of types that the objects must match.
 * <p>
 * The sorting is done using the score calculated by the {@link StringScorer} of this searcher.
 * 
 * @author Peter De Bruycker
 */
public class CatalogObjectSearcher {
    private StringScorer stringRanker = new DefaultStringScorer();

    public List<Result<CatalogObject>> searchObjects(HistoryTracker historyTracker, List<CatalogObject> objects,
            String query, Class<?>... types) {
        List<Result<CatalogObject>> results = new ArrayList<Result<CatalogObject>>();

        for (CatalogObject object : objects) {
            if (typeMatches(object, types)) {
                // do the matching

                Set<Integer> matchedIndexes = new HashSet<Integer>();
                float score = stringRanker.score(object.getName(), query, matchedIndexes);

                if (score > 0) {
                    score += historyTracker.getRankModifier(object, query);

                    results.add(new ScoredResult<CatalogObject>(object, score, matchedIndexes));
                }
            }
        }

        Collections.sort(results, new ResultComparator());

        return results;
    }

    private boolean typeMatches(CatalogObject object, Class<?>[] types) {
        if (types == null || types.length == 0) {
            return true;
        }

        for (Class<?> type : types) {
            if (object.hasExtension(type)) {
                return true;
            }
        }

        return false;
    }
}
